Answer 8 key questions about your working arrangement to get an indicative IR35 status. Always seek professional advice for a definitive determination.
This checker helps UK contractors and their clients assess whether a contract is likely to fall inside or outside IR35 (the off-payroll working rules). It scores your engagement against the key HMRC employment status tests.
Note: This checker is for guidance only and does not constitute legal or tax advice. For a definitive IR35 assessment, use HMRC's Check Employment Status for Tax (CEST) tool or consult a specialist IR35 adviser.
This tool provides an indicative result only. IR35 determinations are complex and fact-specific. Always consult a qualified tax adviser or use HMRC's Check Employment Status for Tax (CEST) tool for a formal assessment.
Can you send a substitute to perform the work if you are unavailable, and the client cannot refuse them?
Does the client dictate how, when, and where you perform your work, or can they move you to different tasks?
Are you financially liable for fixing mistakes at your own expense, or do you invest in your own equipment/insurance?
Is there an obligation for the client to offer you work and for you to accept it (Mutuality of Obligation)?
Do you primarily use your own significant equipment or resources to perform the work?
Are you integrated into the client's business operations (e.g., using their email, attending staff meetings, holding a client employee title)?
Are you free to work for other clients simultaneously, even if you choose not to?
Is the engagement for a specific project with a defined end, rather than an open-ended, ongoing role?
| Factor | What it means |
|---|---|
| Substitution | An unfettered right to send a substitute is one of the strongest indicators of being outside IR35. If the client can refuse your substitute, this right is weakened. |
| Control | The degree to which the client dictates how, when, and where the work is done. Greater autonomy for the worker points strongly towards outside IR35. |
| Financial Risk | Bearing financial risk for mistakes, investing in your own equipment, or carrying professional indemnity insurance are indicators of genuine self-employment. |
| Mutuality of Obligation | A lack of obligation for the client to offer work, and for you to accept it, is a strong indicator of outside IR35. Ongoing guaranteed work suggests employment. |
| Equipment | Primarily using your own significant equipment or resources to perform the work is an indicator of genuine self-employment and outside IR35. |
| Integration | The more you are integrated into the client's organisation — using their email, attending staff meetings, having a line manager — the more it resembles employment. |
| Exclusivity | The freedom to work for multiple clients simultaneously, even if you choose not to exercise it, is a strong indicator of being outside IR35. |
| Length of Engagement | Engagements for specific projects with defined ends suggest genuine contracting. Long, open-ended arrangements that mirror permanent employment point towards inside IR35. |